It depends on what else is included in the development. If it is just a stadium then it sounds a bit pricey, but if there is a plethora of other sports facilities/buildings/businesses then maybe it is not so bad.
The actual stadium costs are only 60 million but we have allowed 90m for an art commission by Damian Hurst to get one over Fulham's statue of the local kiddy fiddler Jack Michealson Early ideas are of a giant monkey ****ing a cat sliced in half in a large tank of embalming fluid
But the Emirates cost £390m, Wembley £798m and the Olympic Stadium £468m. Seems surveying is an inaccurate science mate.
150m is actually not a bad price for London - that will include land and also the other buildings such as hotel etc..